Automatically-reversing razor-blade stropper



Dec. 6, 1927. 1 1,651,781

F. N. SPRAGUE AUTOMATICALLY REVERSING RAZOR BLADE STROPPER Filed A112. 24. 1925 5. Xiai Patented Dec. 6, 1927.

v UNITED SATE-S FRANK-7N. srnAGUE, or I-IOLYOKE; COLORADO.

AU'roM TIcntLY-REvERsme RAZOR-BLADE ,srnorrna.

My invention relates to automatically reversing razor blade stroppers.

-The main object of the invention is to provide a device of this character comprising a handle, a strop engaging plate in slidable relation therewith, and a blade holder pivotally' supported on' said plate holder and so connected with the handlethat the stropping movement of the handleacts to swing said blade holder on its pivots in a direction diametrically opposite to the movement of the handle, whereby the opposite sides of the blade are alternately'brought into contact with the'strop, anti-friction balls being interposed between the handle and the strop engaging plate, which insure an initial reverse movement of the handle at the end of each stroke before such movement is transmitted'to the strop-engaging plate.

Further to provide resilient means which act both to cushion theengagement of the razor blade with the strop, and to lift the blade out of engagement with the strop instantly open the release of pressure on the handle at the end of each stroke thereby eliminating the possibility of cutting the strop with the blade.

These and other objects are accomplishedby the invention shown in the accompanying drawings in which: Y

Fig. 1', is a perspective View of= the improved razor blade sharpner as it appears the device, a portion only, of the handle being shown.

when in use in connection with a strop and showing the anti-friction balls which are interposed between the flat end of the handle and the strop engaging plate. 1 1 Fig. 2, is a transverse sectional view of the same on the line of a pair of the ball retaining slots, the razor blade being incontact with the strop. 1

Fig. 3, is a transverse sectional view showing the blade holder in a position the'reverse of that shown in Fig. 2,-the blade being lifted out of contact with the strop underthe action ofits cushioning spring.

Fig. 4, is a longitudinal sectional view of Fig. 5, is a plan viewtion of the handle.

of the flat body por- Fig. 6, is a plan view of the strOp -engag 7 ing plate.

'- Fig. 7 is aview of the blank from which the blade holder is formed. I r Fig. 8, is an enlarged perspective view of the spring which cushions the engagement Application filed August 24,1925. Serial No. 52,080.

of the blade with the strop, and 'which lifts the blade clear of the strop at the end of eachstropping stroke.

Fig. 9, is an enlarged transverse sectional view through thepiv0t pin for the blade holder, and a portion. of said blade holder, showing the manner of connecting the cushioning spring to the said pin and holder, and Fig. 10, is a side view ofone of the pinions which are rigidly secured to the blade holder; Referring to the accompanying drawings: The numeral 1, refers to the handle portion ofthe improved razor blade sharpener, which is preferably stamped from a piece of suitable sheet metal to provide the handle proper, and an'extension 2, which is a continuation of one end of the handle, and is-in the form of a flat plate-like member which is slightlycurved from edge to edge as shown in Figures 2 and 3. A pair of parallel toothed racks 3, are'formed on the plate 2, in the following manner:

irelatively' long transverse slit is formed in the plate near each of its ends, and each of these slits terminates in a. short slit cut at right angles to the longgslit, therebysev'er- .ing-from the plate two strips, each of which is united to the plate along one of its long sides. The long'edge of each strip is formed with" rack teeth 4, and the toothed portions of the strips are then bent up .at right angles to the plate as shown, the racks thus formed leaving slots 5 inthe end portions of the plate, as clearly shown in Fig. 55"

The plate 2, is also provided with four short transverse slots 16, which are arranged in pa1rs,'the slots of each pair being in end to end alignment. pair oftheseslots'are located near each of the racks 3, and the sides of each slot incline slightly so that the slots narrower at theirbottoms than are slightly at their tops, as shown inFig. 4. I Y i In each slot is placed a ball 7, which is of slightly greater diameter than: the narrowtest portion of the slot, and thereforecannot i passthrough the slot, butfprojects' slightly beyond the under side of the plate as clearly shown in Figures 2 and 4. These ballsfare confined inthe slots 6, by a thin metal plate '8, having slots 9, corresponding in arrange ment to the-slots 6, the slots 9being slightly narrower than the greatest diameter of the balls, the marginal edges ofthe slots'9, be-

ing slightly flared, as most clearly shown inFig; 4, so as to better. confine the balls and permit them to roll :treelj i in, their slots'a The plate 8 is secured to the plate 2, by punching projections 2 intheplate 2 from theun'der side thereof, the said punch holes extending only partially through the plate; and these projections' enter h'oles8 in'the plate 8, and the two plates are connected by applying solder at thesepoin'ts, or by electrical welding. This arrangement causes the slots 9 in the plate 8 to accurately register with the slots 6.in the plate 2.

A strop-engaging plate 10, lies beneath the extension plate 2, and in contact with the balls 7, and is also curved to correspond with the curvature of the plate 2.

The plate 10, is provided with upright ears '11, which are formed by severing tongues or'strips from the plate and bend 'ing them up. at-right angles as'shown in Figures 4 and 6.

These ears extend up through the slots 5, in the plate 2, and are provided withbearin gfholes12, in which ispivotally mounted a ,pinor shaft 13 upon which is'secured the improved blade holder 14, which is constructed in the following manner: A plate "141 of the outline shown in Fig. 7, is

stamped from a sheet of suitable resilient metal, and is formed with lateral exten- 'sions 16 midway of its length.

The extensions 16, are formed with longitudinalslots 17, and a slightly-wider longitudinal slot 18, is'formed centrally of the length and width of'the plate. The plate 14* is then rolled upon'itself, centrally of its length to form a tubular portion 19,

'which tightly surrounds the pin or shaft 13,

and the folded portions of the plate immediately adjoining the tubular portion 19'are pressed tightly together, as'shown at 20, Fig. 9 from which point they diverge fora distance and then are'curved toward each other, the curve terminating a short 'distance from the 1 end portions of the plate which arejfiat and parallel and form blade clamping lips 21, as clearlyshown'in Fig ures 2 and 3. g 7

Then theblank 14 is bent or rolled upon itself to form the tubular portion 19, the slots 17 and 18 become circular slots, .and

the slots'l'i, define the'position of toothed disks or pinions 22, which are mounted on the pin 13. WY

The pinions 22, as shown in Figure 110, are

each provided preferably, with six teeth which extend slightly more than half way aroundthe circumference of the pinion, and with a central hole 23, and anotch orrecess 24, is formedin the circumferential edge of the pinion midway between the two-end teeth. The'hole 23, isof the same diameter 1 as the pin 13,- but the recess 24, isofilelss width than the diameter of thehole 23, its width being equal'to'twicethe thickness of the blank 1 1 Before the pin 13, isinsertedin the tubular" portion 19, of the blade holder, ,the pinions 22 are inserted in the slots 17, the folded parts 20 [of the holder fitting tightly in the recesses 24 of the pinions by which the pinions are locked to the blade'holder, an'dthus prevent the folds of the holder from spreading. The ends of the' tubular part 19, are then placed between the ears 11 whichproject up through the slots5, of the plate 2, the opening through the tube registering with the holes 12, in

said ears, and the-pin 18, is passed through the ears and through the tube and through the holes 23,-in the pinion 22.. The pin fits tightly in the tube and: supports the pinions and at the same ti1'ne,prevents the pinions from becomingdisconnected from the blade holder, the pinionsbeing in'mesh with the rack teeth 4, in theplate 2. I Y

"Before inserting the pin, care should-be taken to arrange the parts in the positions shown in-Fig. 1, or in the reverse positions orthe holder should stand in a vertical positionand. centrally with respectto the racks 3; then when the pin is inserted the-move mentof'the handle in either direction will produce the proper swinging theblade-holder. I

WVhen the 'partsare assembled, the pin '13, -'is pivotally mounted in the ears 11,'of?th-e strop-engaging'platef10, which isnot' con nected to the handle, but theEpin-ions 22' bear on the rack teeth 4:,thusholding theplate 1'0, in slidable relation with respect'to the handle, while the blade holder which-is1piv otally connected; to the ears 11 of thehplate 10, is thus indirectly connected to the handle. :v 1

A razor blade 25, is'inserted between the ends 21, of the holder a-ndis clampedbetween them under spring pressure exerted bytthe folded portions tithe holder, and

the blade is'kept'from'violent contact with thestrop as the bladeholde'r swings from movement of the folder, as shown in Fig. 9, an dthe-U- shapedend of the lower bowed portion-27, is likewise passed up through thestraight portion ofthe'slot 18, s'o'that its extremity will engage upper side of the said folded por- 'tions 20, of the'holden-and' the terminal ends of the bowed portions will'then be in p0 sition to' alternately engage the surface of the plate8, as the hol'der swings from right to left, and these terminal ends engage the said plate before the razor blade contacts with the strop, thus cushioning each swinging movement of the holder and blade and thereby preventing forcible engagement of the razor blade with the strop. The spring also prevents cutting of the stropv bythe blade upon each reverse stropping movement of the handle, as the pressure on the blade is released simultaneously with each initial reverse movement of the handle,

thereby permitting the spring to slightly lift the blade holder and thus raise the:

blade out of contact'with the strop. In

order to eliminate the noise occasioned by the striking of the holder against the edge portion of the strop-engaging plate 10, a strip 29, of suitable resilient material, preferably rubber, is cemented to each bladeclamping lip 21, which alternately engage the edges of the plate 10, as the holder swings from one position to the other, as

will be understood by reference to Figures 2 and 3. I

In practice, a razorblade 25, is slipped V between'the clamping ends 21-, of the holder and is held in place by the resilient pressure of said clamping ends. The stropper is then placed upon the strop 80, in the position shown in Fig. 1, so that the plate 10, will bear evenly upon the strop; and the stropper is then drawn back and forth over the strop in the usual manner. Upon the initial movement of the-handle in either direction, the plate 10 remains stationary by frictional contact with the strop, while the rack teeth 4, on the plate portion of the handle engage and turn the pinions 22, therebyswinging the blade holder over in a direction opposite to the movement of the handle; until the blade engages the strop, its engagement with the strop being first cushioned" by the spring S, as above described, after.

which the plate 10, moves withthe handle and the blade is held in more or less forcible engagement with the strop, and at the beginning of the next stroke the blade holder is swung in a reverse direction in the manner above described, and thus the opposite sides of the blade are alternately brought into contact with the strop, as the stropper is moved back and forth over said strop.

,Having described my invention, what I" claim as new and desire to secure by Letters Patent 1s 1. In a razor blade stropper of the character described and which is independent of the strop, a handle having a flat extensionprovided with parallel slots, a strop-engaging plate beneath said flat portion having ears which extend up through said slots, and anti-friction means interposed between said latter plate and said fiat extension, a blade holder pivotally mounted in said ears pinions rigidly connected to said blade holder, rackteeth on said flat extension which turn said pinions on the initial movement of the handle in either direction whereby the blade holder is swung in a direction opposite to the movement of the stropper,- thereby causing the sides of the blade alternately to engage the strop, andmeans carried by the blade, holder for cushioningthe blade holder on either swinging movement whereby forcible striking contact of the blade with the strop is prevented.

2. In a blade stropper of the character described and which is independent of the strop: the combination with a strop-engaging plate having upright apertured ears, a

ject andrack teeth adjoining said slots, a pin pivotally mounted in said ears,- a blade holder rigidly connected to said pin and pinhandle having a flat extension provided with transverse slots through which said ears pro- 7 ions mounted on said pin and rigidly conm nected with said blade holder and 1n mesh with said rack teeth whereby the blade holder is swung over on the initial movementof theliandle in either directiomand anti-friction balls interposed between the said flat extension and the strop engaging plate; of a spring comprising a plurality ofcoils which 7 surround said pin and laterally extending terminal portion which arebent around and then inward their ends engaging opposite sides of said blade holder, said laterally extending portions'engaging the fiat portion of said handle in the swinging movements of said holder, thereby to cushion the engagement of the blade with the strop, and

to lift the blade'out of engagement with the V strop at the end of each stropping stroke.

3. In a blade stropper of the character described a blade holder comprising a metal plate folded centrally to form a tubular portion and blade clamping end portions, said v tubular portion having a central transverse slot and a transverse slot adjacent each end, a pivot pin which passes through said tubular portion, aspring comprising coils which surroundsaid pin and lie in said central slot,

FRANK N. s PRAGUn 

